Noninductive electrical resistor



Oct. 13, 1953 1 KIRBY, JR" E AL 2,655,582

NONINDUCTIVE ELECTRICAL RESISTOR Filed Feb. 1, 1952 INVENTORJ ATTORNEYS Patented Oct. 13, 1953 UNITED STATES PATENT OFFICE Leonard Kirby, Jr., and Gustave Arthur Erickson,

Mendham, N. J., assignors to Mepco, Inc., Morristown, N. J a corporation of New Jersey Application February 1, 1952, Serial No. 269,480

6 Claims.

This invention relates to electrical resistors and has for its primary object to provide a noninductive resistor which can be produced at relatively low cost.

In general, the invention contemplates a resistor which, instead of utilizing the customary alloy wire, consists of a base tape of suitable non-conducting material, such as paper, having a line of resistive alloy suitably applied to it, as by spraying. M will presently be apparent, the alloy line can be applied in any one of a great variety of patterns but in all cases the treated tape is so wrapped upon itself, as by folding or coiling, as to make a compact unit package in which for each portion of the alloy line there is an equivalent portion oppositely disposed with respect to the electrical fields generated by current flow in the line, whereby the respective fields cancel one another.

The invention will be readily understood from the illustrative embodiments shown in the accompanying drawings, of which:

Fig. 1 is a plan of a length of tape having a resistive alloy line applied to it and ready for wrapping;

Fig. 2 is a side elevation of the same tape in a later stage;

Fig. 3 is a plan of another arrangement of the alloy line on a length of tape;

Fig. 4 is a side elevation showing the tape of Fig. 3 in process of being folded;

Fig. 5 is a plan of another arrangement of the alloy line; and

Fig. 6 is a side elevation of a coil formed from the tape of Fig. 5.

In the Fig. 1 form, the base tape I is shown carrying a single straight line 2 of resistive alloy which may be assumed to extend continuously throughout the length of the tape. As will be understood, the total resistance value is established by the length and cross-section of the line of the particular alloy used. In this instance, the line-carrying tape is folded transversely of its length in zig-zag or accordion fashion, as on the fold lines 3 indicated in Fig. 1 and into the form shown in Fig. 2.

Whenever, as in this particular embodiment, the pattern of the alloy line is such that the lines or portions of them on opposite fold faces tend to make contact with one another when the folding is completed and the tape compressed into a flat rectangular unit, its finished form, suitable insulation between the fold faces is provided, as indicated by the reference 4. Such insulation may take the form of a suitable spray coating on the line-coated surface of the base tape or may consist of a superimposed tape of insulating material. As will be recognized, each unit length of the alloy line in the folded up tape lies adjacent and insulated from an equal unit length of the line oppositely disposed so far as the direction of current flow i concerned and, hence, oppositely disposed with respect to the electric fields generated by each unit length of the line.

In the Fig. 3 form, the tape 5 carries an alloy line 6 which is applied in zig-zag form. When the tape is folded up on the fold lines 1, as in Fig. 4, it will be seen that the form of the line 6 avoids contact between the portions of the line carried on the opposed fold faces. In this instance, therefore, no additional insulation is necessary. As before, however, the field generated by each unit length of the alloy line is cancelled by the field of an oppositely disposed length of the line. In both of these forms the alloy line is applied to one side only of the base tape.

While the same is true of the Fig. 5 form, in this instance the base tape 8 has applied to it a double continuous line 9, that is, a line which extends the length of the tape, bridges across at one end, as at 10, and then extends back to the starting end. For convenience of illustration, the line is again shown in straight rather than sinuous form. As shown in Fig. 6 the tape may be Wrapped upon itself in the form of a compact coil, which in some instances may be preferred to the flat package unit produced by folding. It will be apparent that, again, each unit length of the line is oil-set, so far as field generation is concerned, by an equal and oppositely disposed length of line.

It will be understood that suitable terminals (not shown) are connected to the ends of the alloy line either prior to or after folding or coiling of the tape, as may be convenient in the particular case; and that the completely folded or coiled unit may be encased in a protective coating of varnish, lacquer or the like.

In the light of the foregoing exemplification of the principles of the invention, the following is claimed:

1. A non-inductive electrical resistor comprising a base of non-conducting material in the form of a straight, elongated, flexible tape and having a continuous line of resistive alloy applied thereto, the said tape being wrapped upon itself with substantially each unit length of the said line of resistive alloy lying adjacent and insulated from an equal unit length of the said line oppositely disposed with respect to electric fields generated by current flow in said line, the wrapped tape forming a package of a Width equalling that of the tape.

2. A non-inductive electrical resistor comprising a base of non-conducting material in the form of a straight, elongated, flexible tape and having a continuous line of resistive alloy applied thereto, the said tape being transversely folded upon itself into the form of a package unit With the portion of thealloy :line on ,each fold face oppositely disposed to a substantially equal portion of the alloy line'on another fold face with respect to electric fields'generated by 7 current flow in such portions of the alloy line, the said folded tape forminga package of :a width equalling that of the tape.

3. A non-inductive electrical resistor comprising a base of non-conducting material in the form of a straight, elongated, flexible tape .and having a continuous line of resistive alloy applied thereto, the said tape being zig-zag folded transversely of its length, the portions of .the .alloy line on adjacent fold faces being equaland oppositely disposed to each other with respect to electric fields generated by current flow in such portions of the alloy line, the said .folded tape forming a package of a width equalling that of the tape.

4. A non-inductive electrical resistor comprising -a base of non-conducting material in :the form of a straight, elongated, flexible tape and having resistive alloy applied thereto in the form of a line extending continuously from one end of the tape to the other and back to said one end, the said "tape-being wrapped-upon itself with substantially each unit length of the said line of resistive alloy lying adjacent and insulated from an equal unit length of the said line oppositely disposed with respect to electric fields generated by current flow in said line, the wrapped tape forming a package of a width equalling that of the tape.

5. A non-inductive electrical resistor comprising a, base of non-conducting material in the form of a straight, elongated, flexible tape and having resistive alloy applied thereto in'the form of a line extending continuously from one end of the tape to the other and back to said one end, :on the same side of the tape, the said tape being wrapped upon itself with substantially each unit'lengthof the said line of resistive alloy lying-adjacentand-insulated from an equal unit length of the saidline oppositely disposed with espect :to electric fields generated by current References .Cited in the .file .of this ,patent UNITED STATES PATENTS Number Name Date 2,487,695 Cloud u "Nov.8,=19'49 FOREIGN PATENTS N umber Country Date 210,670 GreatBritain Febfl, 1924 633 418 Great Britain .'Dec.19. 1949 

